Last year we were staying at OKW, so got an internal bus to Downtown for breakfast and then got a cab to Premium Outlets and it cost $13. When we were ready to leave we just walked outside and cabs were waiting in the parking lot.
All very easy, very cheap and the shopping was great
I went to Florida Mall last year and it was around $40 for a taxi (one way). That was when it was $2/£1 though, so it wasn't too bad!! Considering the variety of shops and the bargains I got, I felt it was worth the taxi fare and I'm planning on going again this year.
you might want to check out mears, when we first went i was not old enough to hire a car and we got mears bus from disney resort to what was then beltz and then we got on the trolley to florida mall and then mears picked us up and back to hotel, much cheaper than taxis
You can get the i-ride from Premium Outlets all the way up to Prime Outlets. They were still building them when we were last there in Sept 07, had loads of good shops, well worth the trip. Only thing is they are at the other end of I-drive, so takes a wee while.
It's a lot further on foot than it looks, we are used to doing lots of walking even in Orlando (good exercise) but it would take a while and it's not a good idea in the summer months you would get dehydrated and catch a lot of sun on the way. Get a taxi.
If I was only going to one mall (which will probably be the case this trip) i'd choose the Florida Mall as it has the biggest selection of stores, though I suppose it depends what you want to buy. I guess for designer labels the Premium Outlets might be good but we thought it was no better than Cheshire Oaks and won't be bothering again.